相关论文: Small Group Dynamics and Extended Gas

We investigate the influence of an interaction between dark energy and dark matter upon the dynamics of galaxy clusters. We obtain the general Layser-Irvine equation in the presence of interactions, and find how, in that case, the virial…

There are several physical processes to remove gas from galaxies in clusters, with subsequent starvation and star formation quenching: tidal interactions between galaxies, or tidal stripping from the cluster potential itself, interactions…

Compact groups of galaxies provide a unique environment to study the evolution of galaxies amid frequent gravitational encounters. These nearby groups have conditions similar to those in the earlier universe when galaxies were assembled and…

Within the standard framework of structure formation, where clusters and groups of galaxies are built up from the merging of smaller systems, the physical properties of the intracluster medium, such as the gas temperature and the total…

We present two projects related to interaction in the Virgo cluster. In the first section we draw a quantitative comparison of the distribution of the galaxies and the intra-cluster gas taking into account that the Virgo cluster has an…

Observing the neutral Hydrogen in galaxy clusters provides crucial insights in the physical processes that influence the evolution of gas-rich galaxies as they migrate from the lower-density filaments through the cluster outskirts into to…

The cluster environment is the site of important transformations in galaxies at a relatively recent cosmological epoch: the galactic morphological types and star formation activity have evolved significantly during the last few Gyrs. How is…

Selected results from recent studies of star formation in galaxies at different stages of interaction are reviewed. Recent results from the Spitzer Space Telescope are highlighted. Ideas on how large-scale driving of star formation in…

Clusters of galaxies generally form by the gravitational merger of smaller clusters and groups. Mergers drive shocks in the intracluster gas which heat the intracluster gas. Mergers disrupt cluster cooling cores. Mergers produce large,…

We study how the gas in a sample of galaxies (M* > 10e9 Msun) in clusters, obtained in a cosmological simulation, is affected by the interaction with the intra-cluster medium (ICM). The dynamical state of each elemental parcel of gas is…

Poor groups of galaxies are the repositories of most of the baryons in the local Universe and are environments in which galaxy evolution is likely to be both more recent and simpler than in the cores of rich clusters. Yet we know little…

Interactions and mergers play an important role in regulating the physical properties of galaxies, such as their morphology, gas content, and star formation rate (SFR). Controversy exists as to the degree to which these events, even…

Galaxies must form and evolve via the acquisition of gas from the intergalactic environment, however the way this gas accretion takes place is still poorly understood. Star-forming galaxies are surrounded by multiphase halos that appear to…

In the local Universe, galaxies in groups and clusters contain less gas and are less likely to be forming stars than their field counterparts. This effect is not limited to the central group/cluster regions, but is shown by recent…

As the formation of cosmic structure continues to proceed, we observe one of the latest stages of this process in mergers of clusters of galaxies with other clusters, groups, and galaxies. The X-ray emitting hot plasma of these systems can…

Galaxy merger simulations have explored the behaviour of gas within the galactic disk, yet the dynamics of hot gas within the galaxy halo has been neglected. We report on the results of high-resolution hydrodynamic simulations of colliding…

The bulk of the molecular gas in spiral galaxies is under the form of cold H2, that does not radiate and is only suspected through tracer molecules, such as CO. All tracers are biased, and in particular H2 could be highly underestimated in…

In this review, I discuss some highlights of recent research on molecular gas in galaxies; large-scale CO maps of nearby galaxies are being made, which extend our knowledge on global properties, radial gradients, and spiral structure of the…

Cold interstellar gas clouds provide an exciting new method to discover dark matter. Their immense size makes them uniquely sensitive to interactions from the heaviest, most rarefied dark matter models. Using gas cloud observations, we…

A recent survey of the Galaxy and M31 reveals that more than 90% of dwarf galaxies within 270 kpc of their host galaxy are deficient in HI gas. At such an extreme radius, the coronal halo gas is an order of magnitude too low to remove HI…